1. Field of the Invention
The present invention relates to an electronic device that has a dust-proof section over an opening of a housing thereof. In particular, it relates to a microphone having a dust-proof section.
2. Description of the Related Art
As disclosed in Japanese Patent Application Laid-Open No. 2004-328231, it is common practice to cover a sound aperture of a microphone with a cloth, such as a nonwoven fabric, to prevent entry of a foreign matter or dust from the sound aperture.
However, according to such a conventional dust-proof measure, a cloth has to be attached to a microphone with a double-sided tape or adhesive after fabrication of the microphone is completed. Thus, there exists an additional step of cloth attachment after assembly of the microphone. The cloth attachment step is difficult to automate, so that the entire fabrication process including the dust-proof treatment has not been able to be automated. In addition, the cloth cannot endure the heating during the soldering of the microphone in a reflow furnace. That is, the fabrication process including the cloth attachment step has not been able to be automated because of the poor heat resistance of the cloth or the like, too.
Another dust-proof measure is to cover a sound aperture of a microphone with a mesh member made of stainless steel. This measure also requires a step of covering the opening with the mesh member in addition to the microphone assembly step. Thus, this measure also has a problem with automation. In addition, a scrap of mesh member may be produced during processing of the mesh member, and the scrap may enter the microphone as a foreign matter or dust.